FXUS63 KMKX 150523 AFDMKX Area Forecast Discussion National Weather Service Milwaukee/Sullivan WI 1223 AM CDT Thu Oct 15 2026 .KEY MESSAGES... - Widespread rain will spread into southern WI by this afternoon. Lightning is not likely, but possible. - Increasing northwest winds gusting 30-40 mph Friday especially along the lakeshore, with higher gale force conditions likely over Lake Michigan. - Colder end to the week with overnight temps trending to around freezing for Friday night into Saturday morning. && .SHORT TERM... Issued 1222 AM CDT Wed Oct 14 2026 Overnight through Friday: The satellite is showing widespread lower clouds across most of southern WI, with potentially a few holes along the lakeshore at times. With the low level moisture on the northeast/east flow persisting through the night, expect the low clouds to remain in place as well. The clouds and steady breeze will keep temperatures in check tonight, although lows will be in the upper 40s to around 50. A plume of moisture will ride up into southern WI on a stiff low level jet today. This is coincident with the right entrance region of a strong upper jet and a mid level shortwave trough. Meanwhile a stronger mid level trough over southern Manitoba will amplify over the Dakotas and slide into MN this evening. This will help with cyclogenesis of the surface low tracking from MO to lower MI. We can expect rain to spread into southern WI mid to late morning. It will be fairly steady on breezy easterly winds. While a couple lightning strikes are not impossible this afternoon along the 850mb warm front over southern WI, lightning is not likely due to limited instability. Most of the precip will fall this afternoon with a 60% chance of exceeding a half inch within those 6 hours (HREF and REFS probs). The rain will become lighter and more showery after the low passes and winds become westerly after the low exits this evening. We will see an increase in the winds with gusts up to 25-30 mph early Friday due to the strong cold air advection, cyclogenesis and pressure gradient. Blustery northwest winds are expected all day Friday. The peak gusts should be later in the day and into Friday evening as the strong and amplified upper trough passes overhead. The 850mb temps will dive into the single digits below zero during this time. Then northerly winds will gradually diminish Friday evening. There should be a weak enough pressure gradient as high pressure noses into south central WI Friday night to allow for decoupling and therefore a sharp drop in temperatures. The low is expected to be at or below freezing by early Saturday morning. Frost/freeze headlines will likely be needed. Cronce && .LONG TERM... Issued 1222 AM CDT Wed Oct 14 2026 Saturday through Wednesday: Temperatures will quickly recover on Saturday as the low exits and strong high pressure sets up over the Midwest. Yet another surface trough developing in the Northern Plains will keep our pressure gradient tight over WI on Sat, so expect breezy southwest winds (but only to around 20 mph) and highs recovering into the mid to upper 50s. Breezy southwest winds will continue Sunday and highs should manage to reach 60. The warm-up will continue through Thursday as we largely remain in southerly flow. Highs will be in the 60s, but get up to around 70 by later in the week. The weather will remain largely dry from Saturday through Thursday. There is one weak shortwave that cold bring a period of clouds and a few sprinkles on Monday. Cronce && .AVIATION... Issued 1222 AM CDT Wed Oct 14 2026 Clouds with bases around 3500 ft are expected to lower to MVFR through the night. Expect lowering ceilings to IFR (and potentially LIFR) by early this afternoon as steadier rain overspreads southern WI on easterly winds as low pressure tracks across northern IL. The rain will become lighter as winds switch to the north- northwest this evening. Visibility with the rain this afternoon should be reduced to around 3SM with the assistance of some patchy fog. Cronce && .MARINE... Issued 1222 AM CDT Wed Oct 14 2026 Winds will gradually become easterly overnight into late morning as high pressure around 30.3 inches slides through the region. The stronger winds are expected across the southern half of the lake during this time. Low pressure will deepen to around 29.5 inches as it shifts into the eastern Great Lakes later today through Friday. Expect a northwesterly wind shift to ramp up and increase to gales and nearing storm force at times Friday, on the backside of the departing low pressure while a strong high pressure around 30.7 inches builds to the west. Thus will maintain a Gale Watch for all the open waters of Lake Michigan Friday morning into Friday night. As the high sinks toward the Ohio River Valley on Saturday, strong low pressure around 29.1 inches will develop in northern Manitoba. The tight pressure gradient may bring southwest gales to Lake Michigan on Sunday. Cronce && .MKX WATCHES/WARNINGS/ADVISORIES... WI...None. LM...Small Craft Advisory...LMZ644-LMZ645-LMZ646 until 4 PM Thursday. Gale Watch...LMZ643-LMZ644-LMZ645-LMZ646...10 AM Friday to 10 PM Friday. Small Craft Advisory...LMZ643...7 AM Thursday to 4 PM Thursday. Gale Watch...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565- LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868- LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...10 AM Friday to 1 AM Saturday. && $$ Visit us at weather.gov/milwaukee Follow us on Facebook, X, and YouTube at: www.facebook.com/NWSMilwaukee www.x.com/NWSMilwaukee www.youtube.com/NWSMilwaukee